Archive for August, 2013

My long-standing, ongoing, preoccupation with coarse/filter grinding (amongst all other things coffee) receded just a little recently, if only briefly, and was diverted more towards water.

This brief shift away from grind was brought about by various factors (such as purchasing a Tanzania earlier this year for home, my ongoing experiments and reading, and recent experiences of brewing the same coffees in different locations; with Brita filtered Lincolnshire water and unfiltered local tap water at home in Wales, with the same brewing devices, and the same techniques and parameters).

This lead me to some research, and experiments with bottled mineral waters (mixed to match the SCCA ideal TDS with a perfectly neutral PH, and also various degrees either side with unmixed brands), and also to purchase a Brita filter for home tap water for testing also.

Some months ago, whilst delving into water more deeply for the first time, I also contacted Welsh Water, and received some wonderfully prompt and extensively detailed info (grinder manufacturers and grinder retailers so often seem to take a completely different stance, but that’s another story) about local water, the meat of which was as such:

“There is no regulatory limit for hardness (in Caerphilly the hardness is approximately 53.5mg/l as CaCO3 ((moderately soft)) and in Cardiff centre it is approximately 100.3mg/l as CaCO3 ((slightly hard)))”

During this, I’ve been trying to keep brewing/pouring techniques and parameters, grind and batch sizes, fairly consistent, or even identical, as well as sticking to only a few brewing devices (I own a lot), to try to isolate the changes brought about by the water (and much of the same applies to continued experiments with grind as well – see below).

These are some useful links to read if you are also interested in looking at water:

Anyway, after that diversion, I’m definitely back onto aspects of grind. I am currently DIY modifying my Tanzania grinder (at home) to optimise its performance for its general use as a single dosing grinder, with a view to eliminating popcorning (and the potentially negative effects on grind consistency and uniformity of this phenomenon). It seems I am not able to own a grinder without modifying it some way (early on, I modified our Anfim Super Caimano 2nd revision espresso grinder at work with a piece of metal that I knocked-up, which now gives us roughly twice as many grind steps as usual – effectively making the grinder as close to stepless as possible …without actually making it stepless, that is).

It came from thinking *Sure, the Tanz is good, but it could be better (although all grinders could be better!). How can I make it (even) better?* This is work in progress. I’m currently trialling various variations (and there are many, many possibilities), and sourcing parts. This is within ‘spare’ time. As with everything else in coffee preparation, any change you make changes everything else, so I’m currently tinkering, and then constantly reassessing, during these modifications, as each change is made. After these initial experiments, I might also investigate the route of having a bespoke auger made, if necessary…

For those wishing to look at some information regarding this subject, here are some links.

This particular link line-up seems to be a bit of an HB fest, sorry, but sometimes that’s just how it is – when the topics just aren’t to be found being explored, or at least aired, elsewhere… Admittedly, many of these links refer to grinding for espresso, with espresso grinders, rather than coarser, filter grinding and grinders – but the ideas involved are still relevant. If anything this topic might be especially pertinent when it comes to filter grinding. Whilst consistency from grind to grind is of course absolutely crucial for espresso, and shot consistency, it’s generally accepted that ‘ideal’ espresso grind actually requires a wider, Bi or multimodal, less uniform profile, built-in, as a necessary and desirable quality (this is the grind profile produced by professional espresso grinders, and the brew method has therefore developed around this grind to the extent it is considered necessary for correct execution of the process. There are some interesting discussions and experiments going on at the moment exploring uniform grinding for espresso – but this is a rather separate, fringe debate, and not normal practice). Popcorning could therefore potentially even deliver something positive to this requirement, provided the damaging effects are simultaneously managed somehow, and grind settings are also adjusted accordingly to compensate. Whereas for coarse grind brew methods, and grinders, a grind profile that is as uniform as possible is generally considered optimum (again, a popular consensus, not necessarily gospel). So, it might be that the effects of popcorning, complicated and perhaps exacerbated by the scenario of single dosing various different weights, at significantly different grind levels (from medium fine through to very coarse), in terms of potentially widening (or altering) particle size distribution, is even more detrimental for coarse brew methods (and for the best grinders purpose-designed for these brew methods and grind levels), than it is for espresso. Just my own conjecture. During these modifications, it has been interesting to note that the flow of grounds from a (coarse, filter) grinder is in some ways (loosely) reminiscent of the flow of espresso during a shot, in that it is not simply the same from beginning to end; different sections of the event have a different make-up (the latter is well documented, whereas the former is not). The uniformity and distribution of particles in a single dosed sample of filter grind is a little different at the start, through the middle, and at the end (from unconfirmed casual observation, mostly). And this changes with any and every change you make to the way in which you feed beans into the burrs when grinding. Trying to eliminate this variance throughout the portion/dose (which naturally affects the end profile), and homogenise the output as much as possible, is my current quest.

This comes at a fortuitous time, as I’m also currently in the process of sourcing a new filter and press grinder for work for the plan cafe, and am researching the options …bearing much of the above in mind.

So, as I said, back onto grind – for my sins!

Had a sudden thought one weekend recently, and it turned out that my phone and my thermometer agreed sublimely on the current ambient temperature in my garden. I liked this! No proof that either source was actually reliable, but it made me smile, and gave me some reassurance that the measurement of temps in my Paico might be correct enough, before the perpetual nagging feeling that I might need to recalibrate the thermometer, had chance to take hold before brewing..!

At work, my occasional photography these days has shifted a little away from latte art, more towards simple observation of espresso crema, which feels like a logical progression, after all. Latte art is the more obvious show stopper, that screams *Look at me, aren’t I stunning?!* (and yeah, sure, it is), whereas espresso crema, is equally, if not more beautiful, complex, and mesmerising – but in a much more subtle way, on a smaller, more micro scale, that is easy to overlook (although these assertions are undoubtedly the obsessive barista in me talking!). And in fact, it’s (much) harder to control and master – to sustain and predict, with repeatability. And much more important. Even pretty great latte art eventually seems like child’s play in relation to the many other aspects of coffee, including crema. Naturally, I’ve been aware of, and enchanted by, crema for a long time. Aesthetically, it is beautiful, and objectively it is also charged with useful indicators, and as a barista, that makes witnessing its subtleties all the more alluring. But it is perhaps more recently, over the last couple of years, that I have become more in-tune with and watchful of these visual indicators, and have developed a more heightened awareness of the many indications and messages that crema can hold. Visual assessment of crema alone, is valuable, informative, and captivating, for me, and as something I spend a lot of time regarding, both from aesthetic and objective points of view, it’s nice to take the odd picture here and there too (although, as I also take quite a lot of pictures of spent manual filter coffee beds at home, for instance, I might not be the best representative for what is ‘interesting’ subject matter…). No fancy camera or lenses. Just some simple snaps to try to capture it. And in most cases, only the finished surface as well. Crema is a whole subject area in itself, of course, and you can delve pretty deep into the science, if you wish (I recently read one of Illy and Navarini’s famous articles “Neglected Food Bubbles: The Espresso Coffee Foam” which is one example), and there are many, many aspects of it which you can explore. But what I’m referring to here is simply observation of the colour, patterning, and textures, from both an aesthetic point of view, and from the point of view of correlating these visual indicators to taste-promise, using a mental landscape or catalogue compiled over countless observations and tastings. Of course, visual indicators are just that – only indicators, and not a total guarantee of success. And, the visual differences between an ok, but significantly flawed shot, and a lovely one, can be very subtle, even indistinguishable (and the variables that can lead to these variations are of course even more subtle). But nevertheless, there are often occasions when you just know; when these appearances within the crema surface make me virtually certain that there’s a success in the cup, due to this recognition of signs, from the catalogue of experiences (although admittedly, this intuition and assurance is also guided by other aspects during the whole shot making process as well, such as how the dosing looks and feels, what the flow rate and characteristics are like, what the aromas during and after brewing are like, etc, with the appearance of the finished surface being just one key indicator).

As with all things coffee though, the whole thing is very equipment, and coffee, dependant (not to mention technique!), and the attractive visual appearances that indicate potentially successful shots on one set-up might be different to another. Different machines, grinders, baskets (volume, shape, diameter, hole type, etc), doses, brew ratios, roast levels, bean types, techniques, naked or spouted handles, cup types, etc, etc, will all affect the results, and different combinations will produce different shots, and perhaps different indicators. Super tight, heavy updose, dense shots tend to work less well on our set up, taste-wise, for me (and rarely represent coffees well), and so this is not how I brew, generally, and therefore these visual indicators at our parameters will be somewhat unique, and slightly distinct from those brewing with different parameters and equipment (although saying this, there are, I think, certain common, recognisable elements which are fairly reliably and universally indicative of either warning signs, or positive information, about shots). Some people will also have specific preferences, some will have higher, or lower, expectations, and some a deeper, more evolved awareness. But gradually developing an affinity with what constitutes the appearance of likely successful, or at least acceptable, ballpark, crema produced by one’s own set-up, however modest or lavish the equipment or the results may be, within each set of given limitations, is valuable.

And speaking of crema, (nearly) every day, I continue to record basic espresso brewing notes/parameters/observations, which run into the many 1000s of words per month (not including similar notes at home regarding filter brewing subjects, as mentioned above, and others). I feel such notes are so highly equipment, site, and coffee specific, as to not be of any practical use to others, which is why I never see any value in publishing them. Perhaps this same reasoning is why there is, understandably, really so little concrete, in-depth, practical brewing information around on the web, other than the usual, rather vague, generic, often repeated overviews (although there are those going to the effort to make some available, and meaningful, to whom we should all be grateful). The variances between everyone’s equipment, grinders, parameters, techniques, and water, etc, is so vast. It’s easy to say “such and such recipe was amazing!“, but how useful is that information to others, practically? Not that it can’t be useful, but to make it meaningful takes some time. And, the process is highly prohibitively time-consuming for me as it is (even just to log data and observations, of dialling and continued brew settings and parameters throughout each day, in a rushed sort of shorthand that only really makes sense to me), without then also trying to round these up into any sort of interpretable, digestible form that would actually be suitable or useful for others. And so, I mention these notes occasionally, only because I personally find the process useful and valuable – and would recommend it as a learning tool to anyone, within their own practice.

Simply mentioning the subjects I’m looking at as I go along, alluding to the issues related, and providing links to some of the further research that I’ve been looking at myself, sometimes feels like the most helpful approach.

In other news…

Here’s a link to a nifty little Instagram freepour video of me pouring a mocha at the plan, created by Ace customer, Walid, a couple of weeks ago: